Potassium hydroxide periodates

Water-activated cells and batteries are supplied sealed. The caustic (potassium hydroxide) electrolyte and the lime flake are present in Ae dry form. The cell is activated by removing the seals and adding the appropriate amount of water to dissolve the potassium hydroxide. Periodic inspection and addition of water are the only required maintenance. 

The addition of powdered potassium hydroxide (about 20 per cent, of the weight of the carbon disulphide) reduces the refluxing period necessary to complete the reaction. 

Trivalent complexes of biguanide and periodate are also prepared commercially for water sanitation. The trivalent silver periodate, for example, is prepared by the action of potassium periodate and potassium hydroxide on Ag O ... 

On the other hand, both chrysotile and the amphiboles exhibit a high degree of chemical inertia towards strong alkaHes over extended periods. At high temperatures, reactions with alkaHes (NaOH, KOH, Ca(OH)2) become significant over relatively short periods for example, crocidoHte was reported to be attacked by potassium hydroxide above 100°C (22). 

Cyalohexylideneaaetonit ri-le. A 1-L three-necked, round-bottomed flask equipped with a reflux condenser, mechanical stirrer and addition funnel, is charged with potassium hydroxide (855 pellets, 33.0 g, 0.5 mol. Note 1) and acetonitrile (250 ml. Notes 2 and 3). The mixture is brought to reflux and a solution of cyclohexanone (49 g, 0.5 mol. Note 4) in acetonitrile (100 mL) is added over a period of 0.5-1.0 hr. Heating at reflux is continued for 2 hr (Note 5) after the addition is complete and the hot solution is then poured onto cracked ice (600 gl. The resulting binary mixture is separated... 

The reaction time depends on the quality of the potassium hydroxide employed. An induction period is often observed when older potassium hydroxide samples are used, possibly because surface formation of carbonates reduces the solubility of the salt in acetonitrile. An attempt was made to monitor the cinnamonitrile reaction by GLC, following loss of starting... 

A 50% aqueous solution of potassium hydroxide (160 ml) is added at —5° over a period of 30 min to a mixture consisting of 80 g (0.78 moles) N-nitrosomethylurea, 104 g (0.32 moles) 3 -acetoxy-5a-pregna-9(ll),16-dien-20-one and 1 liter of methylene dichloride. The mixture is allowed to come to room temperature and the reaction is continued for 2 hr. The mixture is stirred for 15 min and 1.5 liters of water is added slowly in order to discharge any excess of diazomethane. The layers are separated and the aqueous phase is extracted with 300 ml of methylene dichloride. The organic phase is washed with water dried and concentrated. The residue is triturated with 750 ml of petroleum (bp 100-120°) and the resulting solid is dried in vacuo at 100° to give 106.5 g (92%) of the pyrazoline mp 158° (dec.) [ah 72° (CHCI3) 2 3, 229 mfi (e 1,167). 

This dibromide in 640 ml of methanol is refluxed 2 hr with 35 g of potassium hydroxide in 35 ml of water. At the end of this period the methanol is removed in vacuo, replaced with water and the aqueous solution extracted... 

A solution of potassium hydroxide (5 g) in 8 ml of water is placed in the distilling flask and 25 ml of 95% ethanol is added no boiling chips). The flask is heated in a water bath to 65° and a solution of 21.5 g(0.1 mole) of V-methyl-iV-nitroso-/ -toluene-sulfonamide in 130 ml of ether is added through the dropping funnel over a period of about 25 minutes. The rate of addition should about equal the rate of distillation. When the dropping funnel is empty, another 20 ml of ether is added slowly and the distillation is continued until the distilling ether is colorless. The combined ethereal distillate contains about 3 g (approx. 0.07 mole) of diazomethane and is approximately 0.5 M. 

This material was made up with distilled water to provide 41 g per liter, and the mixture was adjusted to pH 7.0 with potassium hydroxide solution. To the mixture were added per liter 5.0 g of calcium carbonate and 7.5 ml of soybean oil. 2,000 ml portions of this medium were then added to fermentation vessels, equipped with stirrers and aeration spargers, and sterilized at 121°C for 60 minutes. After cooling the flasks were inoculated with a suspension of strain No. ATCC 11924 of Streptomyces lavendulae, obtained from the surface of agar slants. The flasks were stirred for 4 days at 28°C at approximately 1,700 rpm. At the end of this period the broth was found to contain cycloserine in the amount of about 250 C.D.U./ml of broth. The mycelium was separated from the broth by filtration. The broth had a pH of about 7.5. Tests showed it to be highly active against a variety of microorganisms. 

The direct synthetic process is described in U.S. Patent 2,772,280. A solution of 73.3 g (0.332 mol) of (3-aminoxyalanine ethyl ester dihydrochloride in 100 ml of water was stirred in a 500 ml 3-necked round-bottomed flask cooled in an ice-bath. To the above solution was added over a 30-minute period 65.6 g (1.17 mols) of potassium hydroxide dissolved in 100 ml of water. While the pH of the reaction mixture was 7 to 10.5, a red color appeared which disappeared when the pH reached 11 to 11.5. The light yellow solution was allowed to stand at room temperature for 14 hour and then added to 1,800 ml of 1 1 ethanol-isopropanol. The reaction flask was washed twice with 10 ml portions of water and the washings added to the alcohol solution. The precipitated salts were filtered out of the alcohol solution and the filtrate cooled to 5°C in a 5 liter 3-necked round-bottomed flask. To the cold, well-stirred solution was added dropwise over a 35-minute period sufficient glacial acetic acid to bring the pH of the alcohol solution to 6.0. When the pH of the solution had reached 7 to 7.5, the solution was seeded and no further acetic acid added until Crystallization of the oil already precipitated had definitely begun. The crystalline precipitate was collected on a filter, washed twice with 1 1 ethanol-isopropanol and twice with ether. The yield of 4-amino-3-isoxazolidone was 22.7 g. 

To a stirred and refluxed suspension of 17 parts of 1,2-dibromoethane, 7.8 parts of sodium hydrogen carbonate and 50 parts of 2-propanol is added a mixture of 3.4 parts of dl-2-thio-1-phenyl-lmidazolidine, 9 parts of a 20% potassium hydroxide solution in 40 parts of 2-propanol over a period of about 1 hour. After the addition is complete, the whole is stirred and refluxed for an additional 3 hours. The reaction mixture is evaporated. To the residue are added 18 parts of a 15% potassium hydroxide solution. The whole is extracted with toluene. The extract is dried and evaporated. The oily residue is dissolved in acetone and gaseous hy-... 

Cracking of w-alkanes is effectively inhibited by metallic sodium and potassium hydroxide with ABC carrier even under pressure and over a long period of time (Table 2). 

Metallic sodium practically completely retards crecking of heptane and hexadecane over a period of 120 min at 500°C, and in presence of potassium hydroxide with ABC carrier a fraction of decomposed hydrocarbon amounts to 2.1% in case of heptane and to 3.1% for hexadecane. 

Modern solutions fall mainly into three types (a) the plain cyanide bath which contains typically 20-25 g/1 of copper cyanide, 25-30 g/1 total sodium cyanide (6.2 g/1 free sodium cyanide), and is operated at 21-38 C and 110-160 A/m (b) the Rochelle copper bath to which is added 35-50g/1 of Rochelle salt and which is used at 66 C at up to 645 A/m and (c) the high-efficiency cyanide baths which may contain up to 125 g/1 of copper cyanide, 6-11 g/1 of free sodium or potassium cyanide, 15-30 g/1 of sodium or potassium hydroxide, and are operated at up to 6-9A/dm and 65-90 C. Most bright cyanide copper baths are of the high-efficiency type and, in addition, contain one or more of the many patented brightening and levelling agents available. Periodic reverse (p.r.) current is also sometimes used to produce smoother deposits. 

P-n-Propoxypropionitrile, C3H/O. CH2.CH2. CN. Introduce 0 15 g. of potassium hydroxide and 33 g. (41 ml.) of dry n-propyl alcohol into a 160 ml. bolt-head flask, warm gently until the solid dissolves, and then cool to room temperature. Clamp the neck of the flask and equip it with a dropping funnel, a mechanical stirrer and a thermometer (suitably supported in clamps). Introduce from the dropping funnel, with stirring, 26-5 g. (33 ml.) of pure acrylonitrile over a period of 25-30 minutes (1 drop every ca. 2 seconds). Do not allow the temperature of the mixture to rise above 35-45° immerse the reaction flask in a cold water bath, when necessary. When all the acrylonitrile has been added, heat under reflux in a boiling water bath for 1 hour the mixture darkens. Cool, filter and distil. Collect the P-n-propoxypropionitrile at 187-189°. The yield is 38 g. 

Similarly, bases made from the metals of Group I on the periodic table, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH), are called monobasic because they release one hydroxide ion into solution. Bases made up of Group II metals, such as calcium hydroxide [Ca(OH)2] or magnesium hydroxide [Mg(OH)2], release two hydroxide ions and are therefore dibasic. Like acids, any base that is capable of releasing more than one hydroxide ion into solution is called polybasic. 

LaClair (43) has employed the dehydrohalogenation reaction to determine the gamma isomer of benzene hexachloride in the technical product and in dust mixtures. Two identical samples are dissolved in 95% ethyl alcohol and treated with 1 N ethanolic potassium hydroxide at 0° C. for 15 and 50 minutes, respectively. The 15-minute period is sufficient to dehydrochlorinate most of the alpha and the delta isomers without appreciably affecting the gamma. In 50 minutes the gamma isomer is also dehydrochlorinated. The beta isomer does not react under these conditions, and usually the epsilon isomer is present in quantities too small to interfere seriously. 

Another factor to be considered in the use of periodate ion as oxidizing agent is the desired pH. Potassium metaperiodate in solution gives29 a pH value of about 4. For values of pH below 3 to 4, pure periodic acid or acid-salt solutions must be used. For values of pH above 5, solutions containing potassium hydroxide and potassium metaperiodate must be employed.246... 

Although slightly less than an equivalent amount of potassium hydroxide is used, the last of the 1-chloro-l-nitropropane dissolves slowly, and the pH drops sufficiently to allow rapid reaction only after a variable (usually about 3 hours) period of standing. The reaction may also be started by heating one spot on the container with a jet of steam, but it is more convenient and reliable to initiate reaction by cautious addition of acid in the manner described. 

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